There are no existing data from prospective randomized studies focusing on the effect of device closure PFO in patients with cryptogenic stroke. Some observational retrospective studies have shown a beneficial effect in the reduction of recurrent stoke in patients younger that 50 years with cryptogenic stroke when PFO has been closed with a percutaneous device closure(PCD). Some studies have reported an 0% to 3.4% annual recurrence rate of stroke or TIA in patients treated with PDC. The recurrence rate of stroke or TIA in patients with crytogenic stroke or TIA in ordinary antithrombotic treatment is about 5-15 %.